If you want to force all of your site traffic to use HTTPS or a specific part of your website, here is how to do it:

Whole SIte :

RewriteEngine On
# This will enable the Rewrite capabilities

RewriteCond %{HTTPS} !=on
# This checks to make sure the connection is not already HTTPS

RewriteRule ^/?(.*) https://%{SERVER_NAME}/$1 [R,L]
# This rule will redirect users from their original location, to the same location but using HTTPS.
# i.e.  http://www.example.com/foo/ to https://www.example.com/foo/
# The leading slash is made optional so that this will work either in httpd.conf
# or .htaccess context

Specific Directory

RewriteEngine On
# This will enable the Rewrite capabilities

RewriteCond %{HTTPS} !=on
# This checks to make sure the connection is not already HTTPS

RewriteRule ^/?secure/(.*) https://%{SERVER_NAME}/secure/$1 [R,L]
# This rule will redirect all users who are using any part of /secure/ to the same location but using HTTPS.
# i.e.  http://www.example.com/secure/ to https://www.example.com/secure/
# This means if you dont want to force HTTPS for all directories you can force it for a specific sub-section of the site.

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